Cambridge had always prided himself on the breadth of his knowledge. He had friends who were very knowledgable in their own fields but completely lost outside of them. Imperial was an excellent scientist, and when it came to economics, if LSE didn't know it then it wasn't worth knowing. In general knowledge, though, Cambridge had them both beaten.
Back when he was young, it had been possible to know everything there was to know, and he'd clung on tenaciously to that idea. No matter the subject, he was never short of an opinion. He could theorise about electroweak symmetry breaking, tell you the history of Transylvania, or argue over advantageous lines for white when countering the Old Benoni Defence. Usually, he took delight in knowing everything about everything, but he'd discovered that there was a serious drawback.
Cambridge could tell you in great detail exactly how he was losing his mind.
Going insane was bad enough, but going insane and having your own inner monologue commentating on it was more than he could bear. The technical name, according to DSM-IV, was dissociative identity disorder. Some subcultures referred to it as multiplicity. The common vernacular, inaccurately, conflated it with schizophrenia. Cambridge knew all of this, knew its history, sociology, and neurology. What he didn't know was how to deal with the other entities that seemed to be gathering inside his mind.
For the most part, his days were fine. His work kept him too busy and his mind too distracted for any of his cohabitants to do more than occasionally offer a perspective on a problem he was working on. No, his problems came in the evenings when he had time to himself for relaxing. That was when he lost time. He would catch himself falling asleep, before jerking awake and finding himself somewhere else entirely three hours later.
The worst part came when he slept. In his dreams he was transported to another world with all the vividness and verisimilitude of the waking world, but created entirely inside his own mind. There was a park, with children playing on swings, old men sat at a table playing go, and couples walking hand-in-hand through the trees. He could watch them walk along the river, past the serious rowers, and the more leisurely travellers out in punts. He saw, day after day, performances of classical music, and the local cinema which always ran B-movie reruns in the afternoon.
He saw this whole world full of people and experiences and he felt trapped. He knew that it was all created in his mind, and felt that acknowledging it would only give credence to its existence. He didn't want to encourage those parts of his mind that seemed to have a mind of their own. He didn't want to encourage himself.
And so, every night, Cambridge sat alone in a deserted back-alley of the world of his mind, and he pretended it wasn't happening. It didn't help. He could hear the world around him, and even smell it too, sometimes. But mostly, he could just sense it. He may be sitting alone in the dark, but the rest of him was getting on with living.
This went on for some time. How long, he couldn't say. Maybe it had been weeks that he'd been having the dreams, or maybe it had been years. Maybe it had been much longer than that. Cambridge didn't know. But one day, he did know that things were going to change. On that day, as the darkness of his bedroom dissolved into the bright daytime of his interior world, he resolved that he wouldn't be afraid any more. And so, when he found himself in his familiar place on his familiar street, he stood up, and started to walk.
He'd barely turned the first corner when he saw two people, standing there waiting for him. The first was a woman who he figured was younger than he was, but not by much. She was stylish and elegant, and to his eye, quite beautiful. Next to her stood an androgynous looking individual in a brown sweater and a scruffy ponytail.
He was still trying to figure out how to greet two figments of his imagination, when the woman pulled him into a hug and embraced him warmly. "Oh, we're so glad to see you!" she said, with a clear tone of affection. "We've been waiting for you for so very long."
Cambridge stammered a little. Already, this was not going how he'd expected. A nervous "Hi?" was all he managed, but he was rewarded with two wide smiles for it. Apparently, they knew how hard this was for him. He mentally chided himself. Of course they knew. They were him, weren't they?
"My name is Clare," said the woman, "and this is Cavendish." She paused for a second to let Cambridge take this in before continuing, "And we're you. Or you're us. Or we're part of the same thing. It's complicated. But then you already knew that."
Oh great, thought Cambridge, now a figment of my imagination is telling me that my psychoses are complicated.
He didn't say that, though. What he actually said was, "You do realise that you don't actually exist, right? You're just an emergent property of me losing my mind."
He didn't know how he'd expected them to react to this, but he certainly hadn't expected Cavendish to break out into the broad smile of someone grappling with an interesting academic question.
"Well, I suppose that's one way of looking at it. The nature of existence is a tricky thing, after all, and I'm not really the best one to talk about it. Philosophy has never been my thing. I'm the simple sort; I've always gone in for empirical evidence. If something can be observed, if it effects other real things, then it exists. At least, that's how I decided that I existed. I figured I wouldn't be asking the question if I didn't."
"Descartes," muttered Cambridge. "Cogito ergo sum. And I can feel your thoughts. You're a part of me, even though you aren't." He paused to gather his thoughts. "OK, so for sake of argument, let's say that I acknowledge that you exist. What then?"
It was Clare who answered him. "We want you to accept us. Not just to acknowledge us, but to truly accept us. You're a part of us as much as we're a part of you, and it hurts that you'd rather not have to deal with us. You've always been an old-school kind of fellow, I know. It matters to you what's right and what's proper, and you don't see us as fitting with that. But Cambridge, you have to realise that we aren't going to go away. If you try to ignore us, we'll just keep getting louder and louder."
Cambridge didn't reply. He had nothing to say. He knew it would take some time to process the thoughts. He just nodded at Clare to continue.
"Breadth of knowledge has always been important to you, but we, many of us anyway, need something more than that. We need breadth of experience as well. Your life outside is stifled by routine and tradition. Always the same clothes, the same friends, the same hobbies. The world is so much bigger than that, but you don't see it. That's why we created this world, in our heads, to see and do the things we never do outside.
"Personally, I like to pamper myself, and to dress up. Cavendish here loves to build things. Some of the others are at the happiest when they can go out on the river and play Pooh Sticks. And, frankly, you need a break. You're exhausted. You've been running things on your own for too long. Let us help. Please."
For Cambridge, the odd thing was that he felt as if he knew all of this already, somehow. It was like a deeply buried memory that he was remembering for the first time in years. The thoughts were all there, in his brain, but somehow not his. He could feel their rightness. He nodded his assent. It was a simple gesture, and would have been ambiguous to anyone who didn't share his brain, but that was no longer a worry.
It was about time to wake up, he knew. Someone had to go and be Cambridge for the day. He smiled, safe in the knowledge that someone else would take care of it, and set off to explore his new world.